Use an approach to build stanza that do not require a "builder" abstraction

_examples/delegation/delegation.go

@@ -110,7 +110,7 @@ func discoInfoRoot(iqResp *stanza.IQ, opts xmpp.ComponentOptions) {
 			Space: stanza.NSDiscoInfo,
 			Local: "query",
 		},
-		Identity: identity,
+		Identity: []stanza.Identity{identity},
 		Features: []stanza.Feature{
 			{Var: stanza.NSDiscoInfo},
 			{Var: stanza.NSDiscoItems},
@@ -148,7 +148,7 @@ func discoInfoPEP(iqResp *stanza.IQ) {
 			Space: stanza.NSDiscoInfo,
 			Local: "query",
 		},
-		Identity: identity,
+		Identity: []stanza.Identity{identity},
 		Node:     pepNode,
 		Features: []stanza.Feature{
 			{Var: "http://jabber.org/protocol/pubsub#access-presence"},

stanza/README.md

@@ -8,10 +8,11 @@ When creating stanzas, you can use two approaches:
 
 1. You can create IQ, Presence or Message structs, set the fields and manually prepare extensions struct to add to the
 stanza.
-2. You can use `stanza` Builder providing 
+2. You can use `stanza` build helper to be guided when creating the stanza, and have more controls performed on the
+final stanza.
 
-The methods are equivalent and you can use whatever suits you best. The Builder will generate the same type of
-struct that you can build by hand. 
+The methods are equivalent and you can use whatever suits you best. The helpers will finally generate the same type of
+struct that you can build by hand.
 
 ### Composing stanzas manually with structs
 
@@ -28,7 +29,7 @@ Here is for example how you would generate an IQ discovery result:
 			Space: stanza.NSDiscoInfo,
 			Local: "query",
 		},
-		Identity: identity,
+		Identity: []stanza.Identity{identity},
 		Features: []stanza.Feature{
 			{Var: stanza.NSDiscoInfo},
 			{Var: stanza.NSDiscoItems},
@@ -38,19 +39,14 @@ Here is for example how you would generate an IQ discovery result:
 	}
 	iqResp.Payload = &payload
 
-### Using Builder
+### Using helpers
 
 Here is for example how you would generate an IQ discovery result using Builder:
 
-	b := stanza.NewBuilder()
-	iq := b.IQ(stanza.Attrs{Type: "get", To: "service.localhost", Id: "disco-get-1"})
-
-	payload := b.DiscoInfo()
-	identity := b.Identity("Test Component", "gateway", "service")
-	payload.SetFeatures(stanza.NSDiscoInfo, stanza.NSDiscoItems, "jabber:iq:version", "urn:xmpp:delegation:1").
-		SetIdentities(identity)
-
-	iq.Payload = payload
+	iq := stanza.NewIQ(stanza.Attrs{Type: "get", To: "service.localhost", Id: "disco-get-1"})
+	disco := iq.DiscoInfo()
+	disco.AddIdentity("Test Component", "gateway", "service")
+	disco.AddFeatures(stanza.NSDiscoInfo, stanza.NSDiscoItems, "jabber:iq:version", "urn:xmpp:delegation:1")
 
 ## Payload and extensions
 

stanza/builder.go

@@ -1,62 +0,0 @@
-package stanza
-
-import (
-	"encoding/xml"
-)
-
-type builder struct{ lang string }
-
-// NewBuilder create a builder structure. It act as an interface for packet generation.
-// The goal is to work well with code completion to more easily.
-//
-// Using the builder to format and create packets is optional. You can always prepare
-// your packet dealing with the struct manually and initializing them with the right values.
-func NewBuilder() *builder {
-	return &builder{}
-}
-
-// Set default language
-func (b *builder) Lang(lang string) *builder {
-	b.lang = lang
-	return b
-}
-
-func (b *builder) IQ(a Attrs) IQ {
-	return IQ{
-		XMLName: xml.Name{Local: "iq"},
-		Attrs:   a,
-	}
-}
-
-func (b *builder) Message(a Attrs) Message {
-	return Message{
-		XMLName: xml.Name{Local: "message"},
-		Attrs:   a,
-	}
-}
-
-func (b *builder) Presence(a Attrs) Presence {
-	return Presence{
-		XMLName: xml.Name{Local: "presence"},
-		Attrs:   a,
-	}
-}
-
-// ======================================================================================
-// IQ payloads
-
-// DiscoInfo builds a default DiscoInfo payload
-func (*builder) DiscoInfo() *DiscoInfo {
-	d := DiscoInfo{
-		XMLName: xml.Name{
-			Space: NSDiscoInfo,
-			Local: "query",
-		},
-	}
-	return &d
-}
-
-// Identity builds a identity struct for use in Disco
-func (*builder) Identity(name, category, typ string) *Identity {
-	return &Identity{}
-}

stanza/iq_disco.go

@@ -1,27 +1,80 @@
 package stanza
 
-import "encoding/xml"
-
-// ============================================================================
-// Disco
-
-const (
-	NSDiscoInfo  = "http://jabber.org/protocol/disco#info"
-	NSDiscoItems = "http://jabber.org/protocol/disco#items"
+import (
+	"encoding/xml"
 )
 
+// ============================================================================
 // Disco Info
+
+const (
+	NSDiscoInfo = "http://jabber.org/protocol/disco#info"
+)
+
+// ----------
+// Namespaces
+
 type DiscoInfo struct {
-	XMLName  xml.Name  `xml:"http://jabber.org/protocol/disco#info query"`
-	Node     string    `xml:"node,attr,omitempty"`
-	Identity Identity  `xml:"identity"`
-	Features []Feature `xml:"feature"`
+	XMLName  xml.Name   `xml:"http://jabber.org/protocol/disco#info query"`
+	Node     string     `xml:"node,attr,omitempty"`
+	Identity []Identity `xml:"identity"`
+	Features []Feature  `xml:"feature"`
 }
 
 func (d *DiscoInfo) Namespace() string {
 	return d.XMLName.Space
 }
 
+// ---------------
+// Builder helpers
+
+// DiscoInfo builds a default DiscoInfo payload
+func (iq *IQ) DiscoInfo() *DiscoInfo {
+	d := DiscoInfo{
+		XMLName: xml.Name{
+			Space: NSDiscoInfo,
+			Local: "query",
+		},
+	}
+	iq.Payload = &d
+	return &d
+}
+
+func (d *DiscoInfo) AddIdentity(name, category, typ string) {
+	identity := Identity{
+		XMLName:  xml.Name{Local: "identity"},
+		Name:     name,
+		Category: category,
+		Type:     typ,
+	}
+	d.Identity = append(d.Identity, identity)
+}
+
+func (d *DiscoInfo) AddFeatures(namespace ...string) {
+	for _, ns := range namespace {
+		d.Features = append(d.Features, Feature{Var: ns})
+	}
+}
+
+func (d *DiscoInfo) SetNode(node string) {
+	d.Node = node
+}
+
+func (d *DiscoInfo) SetIdentities(ident ...Identity) *DiscoInfo {
+	d.Identity = ident
+	return d
+}
+
+func (d *DiscoInfo) SetFeatures(namespace ...string) *DiscoInfo {
+	for _, ns := range namespace {
+		d.Features = append(d.Features, Feature{Var: ns})
+	}
+	return d
+}
+
+// -----------
+// SubElements
+
 type Identity struct {
 	XMLName  xml.Name `xml:"identity,omitempty"`
 	Name     string   `xml:"name,attr,omitempty"`
@@ -34,7 +87,13 @@ type Feature struct {
 	Var     string   `xml:"var,attr"`
 }
 
-// Disco Items
+// ============================================================================
+// Disco Info
+
+const (
+	NSDiscoItems = "http://jabber.org/protocol/disco#items"
+)
+
 type DiscoItems struct {
 	XMLName xml.Name    `xml:"http://jabber.org/protocol/disco#items query"`
 	Node    string      `xml:"node,attr,omitempty"`

stanza/iq_disco_test.go

@@ -0,0 +1,55 @@
+package stanza_test
+
+import (
+	"encoding/xml"
+	"testing"
+
+	"gosrc.io/xmpp/stanza"
+)
+
+func TestDiscoInfoBuilder(t *testing.T) {
+	iq := stanza.NewIQ(stanza.Attrs{Type: "get", To: "service.localhost", Id: "disco-get-1"})
+	disco := iq.DiscoInfo()
+	disco.AddIdentity("Test Component", "gateway", "service")
+	disco.AddFeatures(stanza.NSDiscoInfo, stanza.NSDiscoItems, "jabber:iq:version", "urn:xmpp:delegation:1")
+
+	// Marshall
+	data, err := xml.Marshal(iq)
+	if err != nil {
+		t.Errorf("cannot marshal xml structure: %s", err)
+		return
+	}
+
+	// Unmarshall
+	var parsedIQ stanza.IQ
+	if err = xml.Unmarshal(data, &parsedIQ); err != nil {
+		t.Errorf("Unmarshal(%s) returned error: %s", data, err)
+	}
+
+	// Check result
+	pp, ok := parsedIQ.Payload.(*stanza.DiscoInfo)
+	if !ok {
+		t.Errorf("Parsed stanza does not contain an IQ payload")
+	}
+
+	// Check features
+	features := []string{stanza.NSDiscoInfo, stanza.NSDiscoItems, "jabber:iq:version", "urn:xmpp:delegation:1"}
+	if len(pp.Features) != len(features) {
+		t.Errorf("Features length mismatch: %#v", pp.Features)
+	} else {
+		for i, f := range pp.Features {
+			if f.Var != features[i] {
+				t.Errorf("Missing feature: %s", features[i])
+			}
+		}
+	}
+
+	// Check identity
+	if len(pp.Identity) != 1 {
+		t.Errorf("Identity length mismatch: %#v", pp.Identity)
+	} else {
+		if pp.Identity[0].Name != "Test Component" {
+			t.Errorf("Incorrect identity name: %#v", pp.Identity[0].Name)
+		}
+	}
+}

stanza/iq_test.go

@@ -37,11 +37,11 @@ func TestUnmarshalIqs(t *testing.T) {
 func TestGenerateIq(t *testing.T) {
 	iq := stanza.NewIQ(stanza.Attrs{Type: stanza.IQTypeResult, From: "admin@localhost", To: "test@localhost", Id: "1"})
 	payload := stanza.DiscoInfo{
-		Identity: stanza.Identity{
-			Name:     "Test Gateway",
-			Category: "gateway",
-			Type:     "mqtt",
-		},
+		Identity: []stanza.Identity{
+			{Name: "Test Gateway",
+				Category: "gateway",
+				Type:     "mqtt",
+			}},
 		Features: []stanza.Feature{
 			{Var: stanza.NSDiscoInfo},
 			{Var: stanza.NSDiscoItems},
@@ -63,8 +63,8 @@ func TestGenerateIq(t *testing.T) {
 		t.Errorf("Unmarshal(%s) returned error", data)
 	}
 
-	if !xmlEqual(parsedIQ.Payload, iq.Payload) {
-		t.Errorf("non matching items\n%s", cmp.Diff(parsedIQ.Payload, iq.Payload))
+	if !xmlEqual(iq.Payload, parsedIQ.Payload) {
+		t.Errorf("non matching items\n%s", xmlDiff(iq.Payload, parsedIQ.Payload))
 	}
 }
 

stanza/xmpp_test.go

@@ -10,6 +10,15 @@ import (
 // marshal / unmarshal. There is no need to manage them on the manually
 // crafted structure.
 func xmlEqual(x, y interface{}) bool {
+	return cmp.Equal(x, y, xmlOpts())
+}
+
+// xmlDiff compares xml structures ignoring namespace preferences
+func xmlDiff(x, y interface{}) string {
+	return cmp.Diff(x, y, xmlOpts())
+}
+
+func xmlOpts() cmp.Options {
 	alwaysEqual := cmp.Comparer(func(_, _ interface{}) bool { return true })
 	opts := cmp.Options{
 		cmp.FilterValues(func(x, y interface{}) bool {
@@ -20,10 +29,12 @@ func xmlEqual(x, y interface{}) bool {
 				if xx == zero || yy == zero {
 					return true
 				}
+				if xx.Space == "" || yy.Space == "" {
+					return true
+				}
 			}
 			return false
 		}, alwaysEqual),
 	}
-
-	return cmp.Equal(x, y, opts)
+	return opts
 }